US2622137A

US2622137A - Nonglare illuminated panel

Info

Publication number: US2622137A
Application number: US88334A
Authority: US
Inventors: Peter Leslie Hurst; Sheppard Edward Alfred
Original assignee: Westinghouse Brake and Signal Co Ltd
Current assignee: Siemens Mobility Ltd
Priority date: 1948-05-13
Filing date: 1949-04-19
Publication date: 1952-12-16
Anticipated expiration: 1969-12-16

Description

Dec. 16, 1952 Filed April 19, 1949 2 Sl-lEETS-SI-IEET 1 1 imam v Dec. 16, 1952 PETER ETAL 2,622,137

NONGLARE ILLUMINATED PANEL Filed April 19, 1949 2 SHEETS-SHEET 2 w MM WWMQQTW Patented Dec. 16, 1952 UNITED STATES PATENT OFFICE Leslie Hurst Peter and Edward Alfred Sheppard, Kings Cross, London, England, assignors to Westinghouse Brake and Signal Company Limited, London, England Application April 19, 1949, Serial No. 88,334;

In Great Britain May- 13, 1948 e This invention relates to mimic diagram panels for railway signalling systems of thekind arranged to provide a representation of railway trackand signal layouts for the purpose of control or information, and has for its object to provide an improved panel of this character.

Mimic diagram panels are now widely employed in railway signal cabins, for example, to provide a signalman with a complete and compact representation of the track layout controlled from the cabin.

As hitherto arranged the diagram panel is plane and is usually mounted above a control panel or console and in the case of complicated layouts or networks the vertical dimension of the panel is somewhat considerable so that the extreme edges of the panel subtend a large angle at the observers eye and render observation inconvenient and fatiguing.

Furthermore a plane panel has the disadvantage that light rays for any natural or artificial source are liable to be reflected in a direction within the range of vision of the observer.

According to the invention, the cross-sectional contour of the panel is curved so as to present a concave surface to the observer the curvature being such that any light from an extraneous source is reflected from the surface of the panel to a point or points invisible to the observer.

The panel, owing to its concave form, enables the whole representation carried thereby to be viewed by an observer through reduced angle of vision as compared with a plane panel, while reflection from an extraneous source of light cannot interfere with observation.

The invention is illustrated by way of example in the accompanying drawings Figures 1 and 2 of which are diagrammatic views in side elevation of mimic diagram panels arranged in accordance with two forms of the invention respectively.

Fig. 1a shows the front elevation of the mimic diagram shown in Fig. 1;

Referring now to Figure 1 and 1A, the diagram panel I is shown as mounted in a trough or casing 2 forming the upper part of a. frame or housing 3 for the control panel or console 4 for the track or conductor layout a mimic representation 20 of which is shown in Fig. 1A and borne by the panel I.

The control panel or console bears devices to be manipulated by an operator positioned in front thereof for the control in any suitable manner of the associated track switches and signals.

It will be seen that the panel I subtends at the eye of the control operator indicated at 5,

3 Claims. (01. 177 311) -i2 an angle ofvision a, the panel I presentinga concave surface to' the operators eye with a radius of curvature indicated by the dotted. line 6 and a centre of curvature at the point I. The dotted lines 8, 9 including the angle of vision (1., indicates the limiting lines of sight of the panel by the operator, and after reflection from the concave surface of the panel I these lines of sight are represented by the dotted lines I0, I I, respectively which as will be seen in the figure converge towards a point beyond an opaque screen l2. The latter is blackened so as to render the screen highly non-reflecting with the result that any image formed by light from an extraneous source, after reflection from the surface of the panel 1 is prevented from being seen by the operator.

In other words all real images produced by reflection from the surface of the panel which are outside the lines of sight I0, II are for this reason necessarily invisible to the operator while the formation of any such image within the lines of sight I0, II is prevented by the opaque nonreflecting screen l2 which intercepts any light rays tending to form this image.

Extraneous natural or artificial light is thus prevented from reaching the eye of the operator by reflection from the panel I and the representation 20 of the track layout borne by the panel is clearly visible to the operator under all conditions.

In the modification shown diagrammatically in Figure 2 the diagram panel I is so located in the frame 3 that the surface of the panel constitutes an extension of the surface of the control panel or console =4, the two surfaces merging more or less smoothly into one another. The lines of sight H), II forming the limits of the angle of vision a. of the operators eye 5 after reflection from the panel I converge towards a point above the trough 2 containing the panel I and are intercepted by an opaque non-reflecting screen l3, the optical effect of this modification being similar to that of the arrangement of Figure 1 already described.

In both forms of the invention the panel I is preferably arranged to be illuminated by internal reflection from a source of light l4 at the upper edge of-the panel as described in the specification of our co-pending U. S. Patent No. 2,591,864 issued on April 8, 1951.

The invention is evidently not limited to any particular construction or arrangement of the diagram or control panel.

Having thus described our invention what we claim is: I

1. Control apparatus for railway signalling systems, comprising in combination, a control panel bearing devices to be manipulated by an operator positioned in front thereof; a non-reflecting opaque screen; and a concave diagram panel situated above and behind said control panel and curved in vertical cross-section such that the image of the eye of said observer reflected at the surface of the diagram panel is absorbed by said screen.

2. Control apparatus for railway signalling systems, comprising in combination, a control panel bearing devices to be manipulated by an operator positioned in front thereof; a nonreflecting opaque screen in rear of said control panel and invisible from the position of said operator; and a concave diagram panel situated above and behind said control panel and curved in vertical cross-section such that all rays of light passing through the position of the eye of said observer and reflected at the surface of the said diagram panel are reflected on to said screen.

3. Control apparatus for railway signalling systems, comprising in combination, a control panel bearing devices to be manipulated by an operator positioned in front thereof; a nonreflecting opaque screen; and a concave diagram panel curved in vertical cross-section situated above and behind said control panel and having said screen arranged along the top horizontal edge thereof, such that all rays of light passing through the position of the eye of said observer and reflected at the surface of said diagram panel are reflected on to said screen.

LESLIE HURST PETER.

EDWARD ALFRED SHEPPARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,168,751 Schuhmann Jan. 18, 1916 1.681349 Krause Aug. 21, 1928 1,737,520 Richardson, Jr Nov; 26, 1929 1,953,555 Frey Apr. 3, 1934 2,003,735 Brown et al June 4, 1935 2,159,095 Madan May 23, 1939